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MG MGF Technical - top gear

is it possible to change the gearing in just 5th gear.

want better top end on lower rev's.

who can do this ?
r.f.j. griffiths

Strewth, you don't ask much do you! I don't know if the racer boys use any different ratios, but I doubt it. Even if different ratios are available (which I doubt), do you really want to be paying for a gearbox removal, complete strip-down and rebuild? I think you should just put up with it as it is.
Mike Howlett

Could try smaller wheels !!!!
M Barnfather

The box is a Honda PG1 - same in the Rover 820, 827, 600, 620, 220, 218, 216, Maestro 1.6, Maestro 2.0, Maestro 2.0 Turbo, Montego.... Prelude, Legend, Civic....

All with different ratio sets - must be easy!
I have a document somewhere that details all the gear ratios for all the applications... I'll try and dig it out and email it to you.

Dave
Dave

The VVC has slightly taller gearing than the 1.8i, so you can swop the complete gearbox. Alternatively, the PG1 gearbox has been used in a number of different cars so different ratios are possible: Look in the archive for details.

Chris
Chris

These are the interesting bits:


800 PG1 Codes

eg. V4DTUT200001

R = close ratio (type3)
V = close ratio (type2)
W = wide ratio (type4)
C = wide ratio (type6)
4 = final drive ratio (4:40:1)
6 = final drive ratio 3.937:1
D = speedo ratio 1.238 (26/21)
speedo drive teeth on the diff, pretty sure all 6 and 800s are 26 teeth.
T = clutch release lever type (Rover 820)
U = uprated specification
T = Torsen differential
200001 = serial number.

Ratios 800 V4DT R4DT W4 C6DTUTH
5TH 0.764:1 0.755:1 0.714:1 0.765:1
4TH 0.935:1 1.033:1 1.033:1 1.033:1
3RD 1.22:1 1.307:1 1.037:1 1.308:1
2ND 1.894:1 1.894:1 1.842:1 1.842:1
1ST 3.250:1 3.250:1 3.166:1 3.167:1
R 3.000:1 3.000:1 3.000:1 3.060:1

600 PG1 Codes

e.g. C6FTUT200001

C = wide ratio (type 6)
S = wide ratio (type 3)
6 = final drive ratio (3.937:1)
4 = final drive ratio (4.200:1)
F = speedo ratio (rover 600)
T = clutch lever type (rover600/800)
U = uprated specification
T = Torsen differential
200001 = Serial number.

200/400 PG1 gearbox codes.

E.G. K4BX200001

K = close ratio
M = wide ratio
V = close ratio (type2)
4 = fd ratio 4.200:1
5 = fd ratio 4.062:1
6 = fd ratio 3.937:1
7 = fd ratio 3.647:1
B = Speedo ratio 1.015:1 (23 teeth IIRC)
S = clutch lever type 2/400
X = clutch lever type 2/400 plus lsd


gearset:

'C' (1)= 3.166 (2)= 1.842 (3)= 1.308 (4)= 1.033 (5)= 0.765

'S' (1)= 3.250 (2)= 1.895 (3)= 1.222 (4)= 0.848 (5)= 0.649

'B' (1)= 2.923 (2)= 1.750 (3)= 1.308 (4)= 1.033 (5)= 0.848

'K' (1)= 2.923 (2)= 1.750 (3)= 1.222 (4)= 0.935 (5)= 0.765

'M' (1)= 3.166 (2)= 1.842 (3)= 1.222 (4)= 0.848 (5)= 0.649

'V' (1)= 3.250 (2)= 1.894 (3)= 1.222 (4)= 0.935 (5)= 0.765

'T' (1)= 3.250 (2)= 1.894 (3)= 1.222 (4)= 0.935 (5)= 0.714

'R' (1)= 3.250 (2)= 1.894 (3)= 1.308 (4)= 1.033 (5)= 0.755

'W' (1)= 3.166 (2)= 1.842 (3)= 1.308 (4)= 1.033 (5)= 0.714

'L' (1)= 2.923 (2)= 1.750 (3)= 1.222 (4)= 0.848 (5)= 0.649

'G' (1)= 3.250 (2)= 1.894 (3)= 1.308 (4)= 1.033 (5)= 0.848

the number that follows the gearset letter on the code tells the final-drive ratio

'4' is 4.200 (15/63)
'5' is 4.062 (16/65)
'6' is 3.937 (16/63)
'7' is 3.647 (17/62)




Hope this helps!
Dave
Dave

Hi. But which ratio uses the F VVC on 5th gear?

Thanks, Valter.
Valter >´99 VVC & '73 BGT<

Standard VVC Box

* First 3.167 : 1
* Second 1.842 : 1
* Third 1.308 : 1
* Fourth 1.033 : 1
* Fifth 0.765 : 1

Close Ratio VVC Box

* First 2.923 : 1
* Second 1.750 : 1
* Third 1.307 : 1
* Fourth 1.033 : 1
* Fifth 0.842 : 1

Stu Dickens

This thread was discussed between 05/09/2006 and 08/09/2006

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